The calendar may say it's spring, but the season doesn't really arrive until Minor League Baseball Opening Day. In small towns and big cities alike, the cry of "Play Ball!" will signify the start of another 144-game odyssey. The only predictable thing about it will be its unpredictability.

With the season kicking off Thursday, MiLB.com presents a brief compendium of what the day -- and weekend -- has to offer. Read on for an overview consisting of premier prospects, notable debuts and significant franchise firsts.

The Best of the Best

MLB.com's authoritative Top 50 Prospects list was released in January, and most of these emerging stars will be suiting up in the Minors' higher echelons. Here's where to find prospect Nos. 1, 3, 5, 7 and 8 (No. 4, Phillies outfielder Domonic Brown, is on the disabled list, and Nos. 2 -- Jeremy Hellickson -- and 6 -- Aroldis Chapman are already in the Majors).

Who: Mike Trout, OF (MLB club: Angels)
Game: Arkansas at Midland
When: Thursday, 8 p.m. ET
In Brief: He's still a teenager, but the hyper-talented Trout possesses talent beyond his years. Rated the top overall prospect by MLB.com's Jonathan Mayo, Trout hit .341 with 10 homers and 56 stolen bases over 131 games between Class A Cedar Rapids and Class A Advanced Rancho Cucamonga last season. He'll make his Double-A debut in Midland, facing a RockHounds squad that features A's shortstop prospect Grant Green.

Who: Bryce Harper, OF (MLB club: Nationals)
Game: Hagerstown at Rome
When: Thursday, 7 p.m. ET
In Brief: It will be difficult to top the crowds that flocked to every one of Stephen Strasburg's Minor League starts last season, but if any player is capable of doing so, it's fellow Nationals first-round pick Bryce Harper. The 18-year-old outfielder is a budding superstar whose professional odyssey begins in Rome. Harper will be suiting up for visiting Suns, who have unofficially dubbed themselves the "Harpertown" Suns for the duration of Bryce's stay. Harper fans will be happy to know that all Hagerstown home games will be on MiLB.TV.

Who: Dustin Ackley, 2B (MLB club: Mariners)
Game: Tacoma at Sacramento
When: Thursday, 10:05 p.m. ET
In Brief: The second overall selection in the 2009 Draft (picked right after Strasburg), Ackley played 52 games last season with Triple-A Tacoma -- and that's where he'll start the 2011 campaign. His numbers last year were solid but unspectacular, but an MVP performance in the Arizona Fall League may serve as a precursor to a breakout season. It all begins Thursday, when Ackley and his visiting Rainiers take on the perennial Pacific Coast League powerhouse River Cats.

Who: Eric Hosmer, 1B; Mike Moustakas, 3B (MLB club: Royals)
Game: Omaha at Albuquerque
When: Thursday, 9:35 p.m. ET
In Brief: The Royals farm system is widely considered to be the best in baseball, and two of the very best will be manning the corners for Omaha. At first base is Hosmer, who made the jump to Double-A Northwest Arkansas last season and hit .313 with 13 homers in only 50 games. Moustakas was a one-man wrecking crew throughout 2010, combining for 36 homers and 124 RBIs in 118 games between Northwest Arkansas and Omaha. Can he be contained much longer?

In addition to Harper, several 2010 first-round picks will be making their professional debuts. Big things are expected from these players:

Who: Drew Pomeranz, LHP (MLB club: Indians)
Game: Winston-Salem at Kinston
When: Friday, 6:30 p.m. ET
In Brief: A 6-foot-5 southpaw out of Ole Miss, Pomeranz was selected with last year's fifth overall pick. His professional debut is slated for Friday against Winston-Salem, toeing the hill in Kinston's home opener. Will the 2010 Southeastern Conference Pitcher of the Year make a smooth transition to the pros? If so, his emergence will be a big part of the K-Tribe's final season. The venerable Carolina League entity is relocating to Zebulon, N.C., in 2012 after more than three decades in Kinston.

Who: Barret Loux, RHP (MLB club: Rangers)
Game: Wilmington at Myrtle Beach
When: April 8-10
In Brief: Loux, a 6-foot-5 right-hander from Texas, was the Diamondbacks' first-round selection -- sixth overall -- in 2010. He could make his pro debut with the Myrtle Beach Pelicans, the new Class A Advanced affiliate of the Texas Rangers, during their opening series against visiting Wilmington. That's because the D-backs declined to sign Loux, citing concerns over a shoulder injury. He became a free agent and signed with the Rangers for considerably less than first-round money. Can he prove his detractors wrong?

Who: Hayden Simpson, RHP (MLB club: Cubs)
Game: Cedar Rapids at Peoria
When: 7:05 p.m. ET
In Brief: A 6-foot, 170-pound pitcher out of a Division II school typically does not translate to first-round material, but the Cubs made an exception for Hayden Simpson. The deceptively powerful right-hander gets the Opening Night nod for the Chiefs, giving fans everywhere the chance to see how he fares in Peoria. The Chiefs' roster also includes outfielder Matt Szczur, who played for the club briefly last season before returning to Villanova to play out his final season of eligibility on the gridiron. The 21-year-old signed with the Cubs for $1.5 million after committing himself to baseball full-time.

New, Old and New Again

In Minor League Baseball, like life itself, the only constant is change. On the stadium front, 2011 features an opening, a return and several surprising revitalizations.

Game: Nashville at Omaha
When: April 15
In Brief: The lone new facility opening in the Minor Leagues this year is Werner Park, home of the newly rechristened Omaha Storm Chasers. The team had played at iconic (and cavernous) Rosenblatt Stadium for four decades, but next week marks the start of a new era. Werner Park possesses the smallest capacity in Triple-A baseball -- just over 9,000, including standing room -- and the intimate environment will allow fans to view prospects from the Royals' stacked farm system up close and personally.

Game: Salt Lake at Tucson
When: April 15
In Brief: After a three-year hiatus, Pacific Coast League baseball returns to Tucson. The stay by the Tucson Padres (or T-Pads, as they are quickly becoming known) in the city may be brief as a new ownership group (led by Jeff Moorad) hopes to move the club to Escondido, Calif., once a new stadium is built. Until that sorts itself out, Tucsonians can again enjoy professional baseball at Kino Stadium. The facility once served as the Spring Training home of both the White Sox and Diamondbacks and also hosted the Sidewinders (the city's previous PCL entrants, now the Reno Aces).

Games: Lansing at South Bend, April 11
Akron at Reading, April 14
Sacramento at Tacoma, April 15
In Brief: Tacoma's Cheney Stadium, Reading's FirstEnergy Stadium and South Bend's Coveleski Stadium are a combined 135 years old, but they're all looking really good for their age after undergoing extensive offseason renovations. Fans at all three parks will enjoy a bevy of new features and amenities, like Coveleski's new center-field entranceway and Reading's greatly expanded team store and concessions. But it's Cheney Stadium that's going to turn the most heads -- the 50-year-old facility is totally new, outside of the playing field and seating bowl.

This story was not subject to the approval of the National Association of Professional Baseball Leagues or its clubs.